freightliner 108SD 2021, Руководство пользователя

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pressure at which the knob automatically comes
out. This pressure should be 20 to 45 psi (138 to
310 kPa).
18. Close the drain cocks, recharge the system, and
completely drain the primary reservoir. On ve-
hicles equipped with a DRM or AD-IS with the air
dryer attached to the reservoir, the secondary
reservoir pressure should not drop below 65 psi
(448 kPa). On vehicles equipped with single
check valves, where the air dryer is not attached
to the reservoir, the secondary reservoir should
not lose air pressure.
19. On tractors only:
19.1 Start the engine and build the system air
pressure to governor cut-out.
19.2 Shut down the engine and leave the park-
ing brakes released.
19.3 Completely drain the primary reservoir.
19.4 Make a modulated service brake applica-
tion by depressing the brake pedal. The
front brakes should apply and release
and the brake lights should illuminate. In
addition to the front brakes, with the
trailer supply knob pushed in, the trailer
control coupling should deliver air during
the brake application.
20. On trucks only:
20.1 Start the engine and charge the air sys-
tem until governor cut-out.
20.2 Shut down the engine and leave the park-
ing brakes released.
20.3 Completely drain the primary reservoir.
20.4 Make a modulated service brake applica-
tion. Both front and rear brakes should
modulate. At a steady full brake applica-
tion, the pressure should not drop more
than 10 psi (69 kPa) within five minutes.
21. Drain all reservoirs and remove the gauges from
the service reservoirs. Close the reservoir drain
cocks.
22. Remove the chocks from the tires.
42–10 WABCO System Saver
Air Dryer Desiccant
Cartridge Replacement
NOTE: The following instructions apply to the
System Saver 1200 Plus and Twin air dryers.
NOTICE
The WABCO System Saver air dryers can use ei-
ther a standard or oil coalescing desiccant car-
tridge. When replacing the desiccant cartridge, it
is very important to use the same type of car-
tridge that was originally installed on the dryer. Oil
coalescing cartridges can be used in any applica-
tion, but require more frequent service intervals
(every 1 to 2 years instead of every 2 to 3 years
for a standard cartridge). Do not replace an oil co-
alescing cartridge with a standard cartridge, as
this may result in contamination and malfunction-
ing of downstream air system components.
Refer to Fig. 15 for cartridge replacement.
1. Drain the air system.
f421292 10/07/2016
1
2
3
1. Seal
2. O-Ring
3. Air Dryer Base
Fig. 15, Desiccant Cartridge Replacement
Brakes
42
108SD and 114SD Maintenance Manual, October 2019
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